This invention relates to a fuel rail that is used in a fuel injection system for an internal combustion engine. More specifically, the invention relates to a new and unique construction for a fuel rail that has particular utility in connection with a V-type engine.
In a V-type engine there are two banks of cylinders on opposite sides of the engine block. When this type of an engine is equipped with a fuel injection system where an individual injector is assigned to each cylinder, fuel is distributed to the injectors by means of a fuel rail. An example of a fuel rail that is adapted to serve a V-type engine is illustrated in U.S. Pat. No. 4,286,531 issued Sept. 1, 1981 and commonly assigned. The fuel rail of that patent comprises two main branches, one serving one side of the engine and the other serving the cylinders on the opposite side of the engine. The branches share a common inlet and a common outlet, and the direction of flow is the same through each branch between inlet and outlet. The inlet is located in the vicinity of one corner of the engine while the outlet is located in the diagonally opposite corner.
The present invention relates to a new and unique construction for a fuel rail, particularly for a V-type engine, which enables the fuel inlet and the fuel outlet to be located at one corner of the engine while only a single tube is disposed along each side of the engine. The invention, in the preferred embodiment, features the use of baffles disposed within circular main tubes that extend along the two sides of the engine. Each baffle divides the corresponding main tube into two flow channels. In each main tube fuel flows in one direction through one channel and then in the opposite direction through the other channel. One of a pair of side by side transversely extending tubes communicates the upstream ends of corresponding flow channels in each main tube while the second transversely extending tube communicates the downstream ends of the other flow channels of the two main tubes. The fuel inlet is teed into the first transverse tube immediately adjacent one main tube while the downstream ends of said other flow channels lead to a base for mounting the fuel pressure regulator and containing the fuel return outlet from the fuel rail. The main tube that contains the pressure regulator mounting base has a twist in its baffle that provides for the proper communication of the two transverse tubes with its flow channels.
The foregoing features, advantages and benefits of the invention, along with additional ones, will be seen in the ensuing description and claims which should be considered in conjunction with the accompanying drawings. The drawings disclose a presently preferred exemplary embodiment of the invention in accordance with the best mode contemplated at the present time in carrying out the invention.